Concrete Crack & Joint Repair

Floors, driveways and garage slabs (horizontal only)

• Loctite PL S20 Self-Leveling: Henkel lists driveways, garage floors, concrete floors and decks, and sidewalks, and says it suits areas exposed to pedestrian and vehicular traffic. Horizontal surfaces only.
• DAP AMP Self-Leveling: DAP lists concrete driveways, garages, steps, patios and sidewalks, and says it withstands foot and vehicle traffic after full cure. Horizontal use only, joints up to 1/2 in wide.
• Sika Self-Leveling Sealant: Sika lists horizontal expansion joints in driveways, garages and sidewalks. For horizontal joints that take traffic, Sika calls for at least 1/2 in of sealant depth.

Walls, foundations and vertical joints

• Loctite PL S10: non-sag, for horizontal and vertical joints, concrete walls, foundations, brick and block walls, and concrete driveways and sidewalks.
• Sikaflex Construction Sealant, four colors: joints in concrete and masonry, wood and metal, and gaps in walls and floors. Sika says it bonds to most construction materials without a primer.
• DAP Concrete Watertight: fills and seals cracks and holes in concrete, mortar and masonry.

Mortar, brick and stucco

• Sashco Mor-Flexx, five colors: repairs brick, stucco, stone, mortar and tile with a textured, mortar look. Sashco says it is not for areas with high foot or vehicle traffic such as driveways, sidewalks and patios.

Prep steps

1. Clean: Sika says joint walls must be sound, clean, dry and free of oil and grease. Savogran Liquid TSP Substitute is a pre-paint cleaner Savogran lists for concrete.
2. Remove loose material: Sashco says to wire brush the crack or chipped area to remove poorly bonded material before Mor-Flexx.
3. Control depth: DAP and Sika call for backer rod when a joint is deeper than 1/2 in. Sashco Closed-Cell Backer Rod comes in 3/8, 5/8 and 3/4 in.
4. Seal and let it cure: DAP says AMP Self-Leveling is water and paint ready in 1 hour.

More: self-leveling concrete sealant, masonry and block waterproofers, clear concrete sealers, and all concrete and masonry solutions.